I have had to walk out of this place on three separate occasions, and will not be trying for a fourth.
This final time, I just needed new stickers. I waited at the counter at the 'Express Line', which is for stickers for less than three cars. I had four different women look at me, and then disappear either to the back office, or to do something else. After waiting in this 'express' line for a half hour without be acknowledged, I gave up and left.
My first two experiences were no better. The service here is the worst.